


Sweetest Sin (You Caught Me Off Guard)

by Hufflepuff0220



Series: Everyone has their own HPHM universe, this one is mine. [1]
Category: Harry Potter: Hogwarts Mystery (Video Game)
Genre: Explicit Sexual Content In Between, F/M, First Crush, First Kiss, First Time, Fluff, Fluff and Smut, Smut, Teen Romance
Language: English
Status: Completed
Published: 2020-07-23
Updated: 2020-07-25
Packaged: 2021-03-04 23:00:33
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 3
Words: 4,431
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25460548
Author URL: https://archiveofourown.org/users/Hufflepuff0220/pseuds/Hufflepuff0220
Summary: Jae Kim was never in her radar.Yet here they are, snogging while making way up to his dorm after he sneaks her in to search for clues at the Gryffindor common room few minutes earlier.
Relationships: Barnaby Lee/Original Female Character(s), Jae Kim/Player Character (Hogwarts Mystery), Talbott Winger/Original Female Character(s)
Series: Everyone has their own HPHM universe, this one is mine. [1]
Series URL: https://archiveofourown.org/series/1877911
Comments: 4
Kudos: 17





	1. A Love That Will Last

**Author's Note:**

> Hello.  
> I just started playing HPHM earlier this year and found AO3 a few months ago.  
> I feel lucky to found these two, make the quarantine period during the Covid pandemic bearable.  
> The reason I try to write Fanfic was to add more fun during my stay-at-home period.  
> I also do it so I could imagine more about Jae Kim, I like him. ;)  
> Anyhow, I kinda fond of Talbott and Barnaby too so I add them as a background story.  
> I hope the story are easy to understand since this is my first fanfic and English is not my main language.  
> So, cheers, and enjoy. (^u^)

* * *

_Say that you love me, say I’m the one / Don’t kiss and hug me and then try to run / I don’t do drama, my tears don’t fall fast / I want a love that will last._   
_Renee Olstead – A Love That Will Last_

* * *

Before her 5th year at Hogwarts, she didn’t even know that Jae Kim exist.  
She wasn’t even aware that they were classmates in Defence Against the Dark Arts and History of Magic before their initial introduction in the kitchen while they served detention.  
Although his gift at their first meeting made a pretty good impression on her, she didn't feel an urge to do anything to get to know Jae Kim better.  
She’s been too busy juggling between her Cursed Vault quest to find her brother and her school work to maintain her good grade student image.  
What is more, she's actually not an easy-to-close-to-others person.  
She usually keep a safe distance from people, mainly because her brother departure left a deep wound that made her have an insecurity that she would always be left behind by the person she cared.  
Whenever she feels an uncomfortable feeling that she is excluded or left behind from something, she will withdraw herself as soon as she can.  
She managed to hide it so well, letting everyone think of her as a happy go lucky girl who bravely search all the cursed vault, showing loyalty to her brother, determined to prove that her brother was not as bad as people thought.  
Yet, underneath all that, she is just a teenage girl after all.  
No matter how thick she build a barrier around her heart, deep down she longs for someone to shatter those in pieces and love her.  
So, she tried to be romantically involved to someone.

The first person who piqued her interest was Barnaby, whom she befriended at the beginning of her year 3 of school.  
She got to know him more when they worked together as Celestial Ball committee.  
He is simple minded, funny, and of course handsome as well.  
She was quite sure that she fancy him, and she thinks that he's fond of her too.  
They even went to the Celestial Ball together, as a date.  
Unfortunately, neither she nor Barnaby did anything to escalate their relationship beyond what happened during the event.  
She hesitated to act more intimately toward Barnaby since she doesn't feel the attraction was intoxicated enough, while Barnaby seems oblivious to know that he should take action if he wants to get past beyond being friend with her.  
Because of that, their relationship returned back to just friends who occasionally flirt with each other.

Then, nearing the end of their year 3, Penny introduced her to Talbott.  
His calmness and mysteriousness ticks her curiousity.  
She realise that she was fallen for him after all the time they spent so much together flying around the castle in their Animagus form.  
She never told anyone that she was interested in Talbott, until one day at the end of her Potion class, Professor Snape took her scribbling note about her crush and read it aloud to everyone in class.  
Blessing in disguised, that accident was what give her the push to ask Talbott out on a date where he, against all the odd, agreed to went with her.  
Their very first date was not going really well, there’s too much intervention.  
But, they started seeing each other much more after school then.  
Their togetherness at that time was mainly studying together in the library, playing with the owls at the Owlery, or flying around castle ground before landing on nearest tree or one of the castle roof.  
They separated for a bit during the Summer Holiday, but reconnected again when they back to school and begin the year 5.  
They also went on a secret Valentine’s day date when Talbott surprised her with a very special evening at the greenhouse and gave her a very special gift whom she kept dearly in her room.  
Of course, she falls harder for him after that.  
Their first kiss happened within the same week with the Valentine’s day.  
On one fine evening, they landed and sit side by side in one of the Hogwarts castle roof after their usual flying date around the castle.  
She started to rambled about things like she usually do without noticing that Talbott are gradually getting closer to her.  
She then went quiet when she felt that Talbott's fingers run along her cheek then slowly moving downward until it brushed her lips.  
Her heart was pounding very loudly at that time, she bet Talbott could heard it.  
Talbott then gently pulled her chin so she face his direction.  
She melt at the sight of Talbott’s deep gaze and she anxiously waited for what Talbott would did.  
She shut her eyes tightly when she felt Talbott face was coming closer to her.  
Then, she felt it.  
Talbott’s lips, warm and smooth, pressed to hers.  
She felt like time was stopping at that moment, letting her savouring the sweetness of proximity she longed for.  
Just a second after that, Talbott was pulling himself away from her.  
Instinctively, she cupped her hands into Talbott's cheeks, pulled him back to kiss her again, passionately.  
After that night, she sometimes wondered what exactly their relationship were.  
Talbott never declared that she was his girlfriend or that he was in a relationship with her, so she did the same.  
Also, because of Talbott aloof personality, they rarely meet where there lots of people around them.  
In the end nobody really knew that their closeness was beyond being a very close friend.  
Especially since they were never spotted together, not even at their one and only class together, which was Transfiguration.  
Around the times she get more things to took care of; school works, cursed vault, and detention, she sensed that Talbott started to keep a distance from her.  
Not knowing why he was avoiding her, triggered her insecurity.  
Initially, she tried to fight her urge to withdrawn herself from him and tried to get closer to Talbott despite the way he avoided her all the time.  
But, after some time, Talbott lacking effort to her standard in closing the gap between them back then, failed her.  
She knew she wanted more, so she decided to stopped approaching Talbott and avoided him back with all her might.  
She turned her attention fully to school works and even drowned herself into her Cursed Vault quests which in the end made her to be tangled on with detention.


	2. Sugar

* * *

_I don’t wanna be needing your love / I just wanna be deep in your love / And it’s killing me when you’re away / Ooh baby / Cause I really don’t care where you are / I just wanna be there where you are / And I gotta get one little taste._  
_Maroon 5 – Sugar_

* * *

In the middle of year 5, she started to notice Jae Kim.  
The way he bravely handle things defiantly, the way he always willing to help her without making any fuss and just believes in her, the way he just blurted around what’s on his mind with no worries about what others may think about him, never cease to amazed her.  
In her opinion, he is a very chill person, though sometimes his morality are questionable.  
Unwittingly, she started to let Jae near her more often outside detention.  
Sitting together in Defence Against the Dark Arts classes, playing exploding snap at History of Magic classes, or just let him accompanying her searching for clues in her Cursed Vault quest.  
She really enjoyed the way he shoot his sarcastic jokes, it never failed to make her laugh.  
The way Jae comes around her smoothly, makes her unconsciously lingered for his presence.

It was just an usual day where Jae sneaks her into the Gryffindor common room and helped her searching for clues.  
After rummaging for a while, she accidentally let a book down from one of the high shelf and nearly hit by it.  
At that instant Jae rushed over her and pulled her inside his arms.  
The book then fell on his head.  
Jae grimaced in pain, rubbing his aching head with one hand, not letting her go from his arms.  
She just stood there, stunned.  
“Are you all right?” Jae asked and checked her all over.  
She blinked at Jae who looking at her worriedly.  
All of sudden she felt stifling heat around her.  
The unexpected closeness from Jae awaken something inside her.  
Her mind stopped working, her desire takes over.  
Instead of saying thank you, she impulsively held his cheeks with both of her hands and kiss him right on the lips.  
She was intending to let go when she felt Jae hands are hindering her from retreat.  
He then returned her kiss passionately.  
She instantly lost at how delicious the taste of Jae lips on hers.  
Wasted no time, Jae inserted his tongue right when she opened her mouth a bit for an air, hungrily tasted every part of her mouth.  
Burned by lust, she complied when Jae pulled her towards Gryffindor dorm stairs, snogging her nonstop.

Jae then letting her lips go right after the door closed, stare at her admirably while holding her firmly in his arms.  
She tilted her head around, realizing that they have arrived at Jae's dorm room.  
She looked up to Jae.  
She can think about where all of this will go.  
She doesn't know about Jae, but this will be her first time doing it.  
She is not a Seer, but her instincts tell her that as long as it's Jae, everything will be just fine.  
She trusts her guts.  
“I may or may not continue with whatever this bring us to when everyone are on Quidditch pitch… “  
Jae let his words hanging unfinished and smile cheekily.  
She poked his chest and grinned.  
Jae just chuckled and started to snogged her again.  
Their hands are now all over their body.  
Without releasing their lips contact, Jae walked and pushed her to his bed until they both fell upon it.  
He then let go of his kiss, pressed his forehead against hers.  
He breathed rapidly, his face flushed to the ears, and his whole body are feeling very hot.  
He dives back right to her mouth, their tongue dancing passionately while Jae’s hands hurriedly thrown away their shoes and socks to the ground.  
He started unbuttoning and opening her shirt, pushing her bra up, exposing her ripe breast and hardened nipples.  
With several attempt, he finally made her shirt and bra to come off, leaving her upper body totally bare.  
She can feel his jaw dropping a bit, aroused by the feast to his eyes.  
Jae then quickly took off his shirt and hoodie out from his upper body.  
Thirst attacked her while she looked at Jae’s slender figure.  
She trailed his body with her fingers, from his neckline to his hips, looking up to him lustfully.  
Jae jolted. Her touch burned him.  
Directed by carnal instincts, he sucked her hardened nipple wildly while his free hand grope her other breast eagerly.  
She gasped at Jae sudden movement and felt that her knickers are dampened.  
He released his mouth from her breast, take a sharp intake of breath before he resume sucking and groping vivaciously, this time the opposite of his action before.  
She realize right away that Jae’s free hand are moving down, slipping inside her skirt and stopping right at the center of her body.  
Jae caressed her clit from outside of her knickers, sending shivers throughout her entire body, makes her accidentally let out a moan.  
Jae’s eyes looked up and widened upon hearing it, he suck her nipple harder while both of his hand are moving on her breast and clit over her knickers excitedly.  
She can feel Jae’s hardened part that are sticking to her legs are getting hotter.  
Her mind went blank when Jae pulled her knickers aside and put his middle finger inside her, moving it in and out of her cunt fast and steadily.  
She squirmed and groaned in pleasure.  
“Are you this wet because of me?” Jae asked with amusement, looking at her with passion burning in his eye.  
She doesn’t answered, biting her lips, trying so hard not to let another moan out.  
Jae doesn’t probe, his focus already shift to dip more fingers to her cunt.   
Feeling ecstatic from all the things Jae did, she can’t stand the urge to make Jae feel good too.  
She instantly up from her position, turning and pushing Jae so his back are leaning against the head of the bed, then she pull down both of his pants and his underwear.  
Jae squinted and let out a groan when she duck down and suck his dick all of once.  
She tried to put everything inside her mouth, moving it in and out recklessly.  
Jae then hold her head with both of his palm, moving it up and down faster and deeper until she started to gag.  
“Whoops, are you okay?” He takes off both of his hands from her head and pull her up so she sits in front of him, staring at her worriedly.  
She nodded, wiping her mouth with her hand, smiling cheekily while staring at Jae who was completely naked.  
Trailing her gaze, Jae look down at his own body and screeches “Hey, this is not fair!”  
She laughed when he tickled and pushed her down to the bed.  
Jae then started to undress her bottom, throwing her skirt and knickers away.  
“Now we’re even.” Jae smirked.  
she just stared at Jae with a grin on her face.  
They paused for a moment, silently looking at each other.  
Jae stroke her face tenderly, his fingers trailed down every inch of her body, then his hand stalled at her hips.  
He slowly mounted her, sucking her skin here and there from her cleavage to her inner thigh, leaving a lot of kiss mark at her body.  
Jae opened her legs, stroked her wet clit, and positioned himself at the middle of her.  
He looked at her deeply, waiting for permission.  
All of her body are heated up when the tip of Jae’s dick are at the opening of her cunt.  
Holding her breath, putting her arms around Jae’s neck, she nod.  
Jae kissed her fondly and slowly, he thrust himself to her.  
When Jae’s dick finally went all in, he groaned, stopped moving, then put his head down at her shoulder, gasping for breath.  
She felt pain and pleasure both at the same time, also feeling filled.  
She tighten her arms around his shoulder.  
They stay still for a while until Jae rise and put his forehead on hers.  
“Are you ok? Does it hurts?” Jae asked her.  
His concern touched her, she softly smiled and shook her head.  
“Just tell me if it hurts you.” He whispered again.  
She nodded.  
Jae started to move his hips very slowly while overlooking her expression.  
At first it feels uncomfortable for her, but the way Jae's looked at her assures her that everything will be just fine.  
She gave herself in.  
She pulled Jae’s face closer and kiss him deeply then she wrapped her legs around his waist and digging her nails into his back.  
A tingly feeling begun to filled her up as Jae hips moves increasingly faster.  
She can't contain her moan any longer at the feeling of delicacy coming from their connected body parts below.  
“Oh Jae!!!” she screeched the moment her inner walls throbbed,sending waves of pleasures to washed out throughout her body.  
Jae groaned at the feeling of his dick being clamped down by her orgasm.  
He pumped wildly after that, trying to catch up the same pleasurably feeling.  
He grunted and closed his eyes when he finally exploded inside her, swamping her cunt with all his cum.  
As the pleasurably waves slowly drifted away, Jae dropped himself on top of her body, exhausted but pleased.  
She patted his back and wrapped her hands around him while she herself was gasping for air.  
“Jae, we need to go.” She finally said after her breathing back to normal.  
Carefully, she rolled his body to the side and raised herself out of Jae's bed.  
Her eyes catch a glimpse of little tinge bloods at Jae's bed sheet but she choose to not say a thing.  
She felt sore but she knew she can’t stay there for too long.  
The Quidditch match are soon to be over, and she is not supposed to be there when all the Gryffindor’s back to their dorm.  
Jae blinked. His brain was still trying to get the hang of what had just happened.  
“Jae, come on.” She called him again, already put all of her clothes back on.  
Jae complied.  
He put his clothes on hurriedly and walked to her, who already waiting in front of his dorm door.  
Before they go, Jae pulled her into his arms and whispered into her ears, “That was amazing.”  
She smile and kiss Jae's lips lightly, then she walked through the door contentedly.

**Notes for the Chapter:**

> Wow, I never thought writing smut are this exhausting.  
> Still working the end chapter.  
> This time back to fluff. xD


	3. Hero / Heroine

* * *

_And I feel a weakness coming on / It never felt so good to be so wrong / Had my heart on lockdown / And then you turned me around / And I'm feeling like a newborn child / Every time I get a chance to see you smile / It's not complicated / I was so jaded_   
_And you caught me off guard / Now I'm running and screaming_   
_I feel like a hero and you are my heroine / Do you know that your love is the sweetest sin?_   
_Boys Like Girls – Hero / Heroine_

* * *

“You shagged Jae, didn’t you???” Tonks blurted ecstatically when they met outside the great hall the next morning.  
She immediately covered Tonks mouth with her hand while looking around, worried that someone would hear what the pink-haired girl babbling about.  
“I don’t know what are you talking about.” She hissed.  
Tonks rolled her eyes.  
“Oh come on. Yesterday Charlie accidentally fell on Jae’s bed while he was about to change clothes after the Quidditch match. He told me that Jae’s bed smells a lot like you. What else might you do in Jae's bed other than shagged him.” Tonks sneered.  
Before she could answer, Jae rushed over from the Hospital Wing direction.  
He stopped right in front of her, shoved a small vial into her hand while trying to speak between his breaths.  
“Drink it, now.”  
She frowns at Jae’s order, confused.  
Still, she complied and drank the vial in one gulp.  
“Done.” She shoved the empty vial back to Jae who carelessly slipped it into his pocket robe.  
“What’s that?” Tonks asked curiously.  
“Pregnancy prevention potion.” Jae answered bluntly.  
She choked and coughed, glaring at Jae while Tonks burst out laughing.  
“What?” Jae shrugged and looked at her nonchalantly.  
“I knew it.” Tonks claimed while her body was shaken so much by her amused laughter.  
“What’s she talking about?” Jae asked her, amazed by the way Tonks laughs uncontrollably.  
Ignoring Jae, she rolled her eyes at Tonks then answered her question.  
“Fine, you got me. Just don’t go around the bush, okay?” She jeered.  
“Damn Jae, I never knew that you were good at taking care of people.” Tonks grinned.  
“Nah, too much work. I just do it for her." Jae smirked.  
She swore she could see a glint of mischief in his eyes.  
“Okaaayy.” Said Tonks while looking at her meaningfully.  
Embarrassed, she simply covered her face with her palms.  
“What on earth did I just get myself tangled to.” She muttered to herself.  
“A charming boyfriend.” Jae answered cheekily, moving to her side, then wrapped her shoulders with his arm.  
Tonks burst into laughter again.  
Her face was now burnt, she could feel it turning red to the tips of her ears.  
Still, she let Jae's arm stay on her shoulders.  
“Jae..” She whined, now holding her head like she had a bad headache.  
“What? I do fancy you, I never hide it after all.” Jae stared straight into her eyes with his free hand stroking her flushed cheek.  
Tonks snorted very loudly.  
“You got it bad now girl, reeeaaaalllyy baaadd.”  
Jae grinned amusedly at Tonks words while the girl by his side just closed her eyes and restlessly shook her head.

  
“So, are we in a relationship now?”  
She started questioning Jae when they had sit comfortably with their back against the wall under the castle gate to the training ground.  
Jae looked at her.  
“You don’t want to?”  
“No.”  
Jae’s mouth opened and his jaw dropped with a shocked look on his face.  
“I mean, it’s not that I don’t want to. I’m just, I don’t know, uneasy about it.” She quickly continued her words before Jae misunderstood anything.  
They indeed hang out together more over the time and she could tell him about anything though sometimes he occasionally respond annoyingly or reply sarcastically, Jae would never judge her or go around telling others.  
Yet she notice that his favourite quotes is 'what a pain' whenever he had things that bothered him, so she got the impression that Jae wouldn’t be interested in a relationship either.  
She bet Jae thinks that being in a relationship is too troublesome, that’s why she never thought that Jae saw her in that light.  
She knows he trusts her, so she trusts him too.  
What happened the day before was based solely on that term.  
That, and her sudden interest in how it would felt to be embraced by him.  
She didn't expect anything more, so she was surprised when Jae casually reckoned they were dating just like that.  
“You seems to pained your arse hard if you're in a relationship Jae, no offense.” She snickered with a flat tone and shifted her head from side to side.  
“You’re right. None taken. But I don’t mind if it’s with you.” Jae stared at her sternly.  
She just stared back at him silently, saying nothing.  
They stared at each other for quite some time before Jae then sighed.  
“Well, what should I do then to convince you?” Jae asked, he seems lost at her lack of response.  
"Just so you know, you’re my first girl of all. I wouldn't want to do this relationship thing if it’s not with you." Jae muttered and looked away when a hint of blush appeared on his face.  
She scratched the back of her head, still not sure how to respond to Jae’s confession.  
Silence fall between them again.  
“Anyway, sorry for being unprepared yesterday. I never really thought that I would need contraception so quickly. I even felt it was all merely a dream, before I woke up to your scent on my bed. It was then that I realised I might knock you up, so I immediately jumped out of bed and running like a mad man to the hospital wing.” Jae tried to uplift the mood with his rambling.  
Still, it seemed like he couldn’t help feeling nervous as his hands awkwardly tugged on the strap of his hoodie while his eyes looked everywhere but at her.  
She blushed remembering the image of what they had done the day before, but then laughs at the visualization of how fretted the-very-chill-and-cool Jae must be up to the point he dares to come asked Mrs. Pomfrey for help.  
She really owes Jae this time, because she didn’t think about it one bit.  
Sometimes she is indeed that reckless.  
Jae raises an eyebrow at her laughter, looking confused.  
“How brave of you asking Madam Pomfrey to give you THAT potion. Didn't she scattered you out with questions?” She asked amidst her laughter and thought this boy really are amusing.  
Jae's awkwardness was overcome by her laughter, he let out a sigh of relief before answering.  
“Well, I just blurted out to her that I never planned to be shagged for the time being. But it happened, and I feel somewhat responsible because I didn’t take precautions beforehand.” Jae slowly approached her, takes her hand, intertwines her fingers, and she let it be.  
However, her eyes widen hearing Jae’s words, and Jae seems to know what she wants to ask next as he continues to explain.  
“No, I didn’t tell for whom I needed the potion. I don't want to cause new trouble for you. Thankfully Madam Pomfrey asked no further. She even taught me preventive spell for that. Though a very long lecture followed me through, until I managed to escape and came to you.” Jae smiled and looked at her with a suggestive gaze.  
She turned beet red.  
“You pervert.” She hissed and smacked his shoulder with her other hand but couldn’t stop herself from smiled back at him anyway.  
“But maybe after this, she will know for sure whom I gave the potion anyway.” Jae grinned.  
She burst laughing then shrugged.  
“That’s inevitable."  
Jae looks relieved, he holds her hand tightly and slowly raises it then kisses the back of her hand while looking into her eyes, clearly expecting her answer.  
She was thinking, about how to give Jae a proper answer.  
Looking back to everything he said and done for her, she thinks he deserved it.  
“Thank you for looking after me Jae.” She said after a moment, stared straight into his eyes.  
“To tell you the truth, you are also my first. I don’t regret it, and I’m glad it’s you.”  
She squeezes Jae's hand which was holding hers, trying to show him that she really meant what she said.  
Jae smiled joyfully.  
He actually had a hunch that he was her first when he saw the bloodstain on his bed sheets before he went to sleep last night though it's so slight, making it unnoticeable if you didn’t look at it very closely.  
Still, Jae’s worried that she regrets it and didn't want to get involved with him anymore.  
Her warm answer lifted his anxiety, that was all he ever need.  
“So, girlfriend?” Jae asks, looking at her expectantly.  
“Girlfriend.” She grinned.  
Jae’s smile reaches his eyes, he’s brimming with happiness with the answer she finally gave.  
He instantly leaned down towards her to pressed his lips against hers, trying to convey all his feeling to her through a kiss.  
A warm feeling crept into her heart and a thought flashed through her mind, it seemed like she was going to like where all of this was going to sail.  
She closed her eyes, enjoyed the kiss Jae gave her, and smiled.

**Notes for the Chapter:**

> Done!  
> For now.  
> I might continue this work later or just write something else, I haven't really think about it.  
> Change the title a bit to match the song. :P  
> Thank you for reading anyway.
> 
> Oh btw to Lara_Kaminari, thank you for your kudos.  
> I actually left lots of kudos at your work when I'm still just guest at AO3.  
> Your works was one of the HPHM fanfic who inspire me to write.  
> Keep up the good work, I root for you. (^.^)


End file.
